KISS. How are they anything more than a gimmick, really? They have some great catchy tunes, but I don't see how any of their songs put them anywhere near in a league with anyone else on this list. As 4bits pointed out, though, I'm pretty sure that Kiss fans are the
only people who think that Kiss is in a league with The Beatles, Led Zeppelin, and the Rolling Stones.
U2 were good at one point at time, and then they became cheesy sellouts. For decades, they've been a totally-overrated mockery of their eighties alterna-rock glory days. Albums like "Joshua Tree" and "October" deserve to have a stellar reputation, but U2,overall, don't deserve to be regarded as legendary rock icons considering EVERYTHING THEY'VE DONE since their last decent record, which was "Achtung, Baby." Zooropa was a hideous mess, and they've just gone for the sellout hit-grabs ever since. They're even worse than Aerosmith when it comes to making generic-sounding radio-friendly corporate sellout pop for the masses.
Everyone else in this list deserves to have the reputations they have.
The Beatles - They made rock'n'roll what it is. Also, Lennon and McCartney had an otherworldly, godly, superhuman gift for melody. Best songwriting duo in the history of rock'n'roll, hands down. Plus, a bunch of iconic songs that are well-loved by all. Yes, they deserve every single bit of the huge reputation they have.
The Rolling Stones - They're just a bit "meh" to me personally, but can't deny the massive impact they've had on rock'n'roll. "Hard rock" would look drastically different if not for the Stones, so they deserve every bit of their huge reputation.
Led Zeppelin - Are the most influential "heavy rock" band of all time. "Hard rock" as we know it, as well as heavy metal couldn't have existed without them - Robert Plant's wailing, John Bonham's crazy drum-pounding and those huge stacks of Marshalls have left an indelible mark on "hard rock" and "heavy metal." They were also a fabulous all-around talented band with great instrumentalists, a great guitarist, a truly vocally-gifted lead singer, and they seamlessly moved amongst many different genres. Yes, they deserve every bit of that huge reputation.
Queen - I don't really get it, they aren't necessarily "rock" enough for me, but Freddie Mercury was a glorious angel of a lead singer, and Brian May a gifted lead guitarist (and astrophysicist!!!) They've penned many iconically classic songs, and I think they more or less deserve their reputation.
Nirvana - Well, they went out at their peak, but they were being talked up as the "Next Great Rock Legends" long before Kurt Cobain went and killed himself. I think they more or less deserve their reputation, although we'll never really know for sure because Cobain died at the peak of his career and didn't have the opportunity to get old and start sucking. I still remember the day it happened - everyone in school was just walking around stunned all day, because he was one of the biggest rock stars on the planet at that time. I can't believe it was 20 years ago.
Metallica - They're the defining heavy metal band, and the entire genre of heavy metal as we know it today basically couldn't have existed without them. Kirk Hammett and James Hetfield are a brilliantly talented guitar duo. Their reputation is well-deserved although, like Aerosmith and U2, they've certainly endured a lot of "sellout" criticism that they've brought on themselves. Metallica would have a better reputation than they currently do if James or Lars had died tragically after "...And Justice For All".
See, we'll never know what kinds of sucky records Nirvana might've made if they'd kept on going for 20 more years. We know all about U2's and Metallica's lame sucky records, because the guys in U2 and Metallica have been blessed with three-decades-long careers. It's not really fair to compare bands like Nirvana to bands like Metallica and U2 and Aerosmith.
I think Aerosmith is kind of overrated. I think they're also kind of underrated. Convincing arguments can be made either way.
Guns'n'Roses were never as great as they could've potentially been, if they hadn't ruined themselves with drugs and infighting and silly spoiled rockstar antics.